High Spatial Resolution Photodetectors Based on Nanoscale Three-Dimensional Structures

Author

Liu, Boyang ; Lai, Yicheng ; Ho, Seng-Tiong

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., Northwestern Univ., Evanston, IL, USA

Volume

22

Issue

12

fYear

2010

fDate

6/15/2010 12:00:00 AM

Firstpage

929

Lastpage

931

Abstract

A high spatial resolution photodetector is designed and realized using a newly developed two-sided nanoscale three-dimensional fabrication technique. Two types of nanophotodetectors with slab and channel structures are fabricated and characterized. By comparison, nanophotodetectors with channel structures show a 10 times lower dark current, higher detection resolution, and signal-to-noise ratio than nanophotodetectors with slab structures. The smallest nanophotodetector fabricated is as small as 100 nm wide. A responsivity of 0.19 A/W at 1310-nm wavelength and 3-V bias for a channelized nanophotodetector is registered, with a photocurrent of 135 nA over a dark current of 1.25 nA. In addition, using a modified near-field scanning optical microscopy-based photocurrent mapping system, we demonstrated a high spatial resolution photodetection of 400 nm using a nanophotodetector with channel structure fabricated.

Keywords

nanostructured materials; optical fabrication; optical microscopy; photoconductivity; photodetectors; photoemission; channel structures; channelized nanophotodetector; dark current; detection resolution; high spatial resolution photodetection; high spatial resolution photodetectors; nanoscale 3D structures; near-field scanning optical microscopy; photocurrent mapping system; signal-to-noise ratio; size 100 nm; slab structures; two-sided nanoscale 3D fabrication; wavelength 1310 nm; High spatial resolution; photodetectors;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2010.2047255

Filename

5445004